Black smoke indicates the fuel mixture is too rich-could be caused by one of the following below:
1. Excessive fuel pressure can be cause by restricted fuel return line
2. Defective Oxygen Sensors.
3. Leaking injectors and fuel pressure regulator.
4. Coolant temperature sensor out of calibration.
5. Restricted air intake system.
Friday, April 6th, 2012 AT 7:06 PM